John Stevens said, "There are no mistakes in Aikido." Several people in this thread have suggested that there is no one size fits all approach, no "best". Different arms, balance sensitivity, musculature and pain threshholds mean that any technique exists only in the moment of that attack. Success is measured not by throws and locks but by moving effectively in a way that delivers you from the danger. Whether uke falls or not isn't very important ultimately. When we focus on tachi waza and move in tandem with our attacker then whatever we have done will be deemed successful.